<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 找出2000-3000之间所有的闰年
        for(i=2000;i<=3000;i++){
            if(i%4==0&&i%100!=0||i%400==0){
                document.write(i+'<br>')
            }
        }
    </script>
</body>
</html>